Function var #

Compute the variance of a matrix or a list with values. In case of a (multi dimensional) array or matrix, the variance over all elements will be calculated.

Additionally, it is possible to compute the variance along the rows or columns of a matrix by specifying the dimension as the second argument.

Optionally, the type of normalization can be specified as the final parameter. The parameter normalization can be one of the following values:

Note that older browser may not like the variable name var. In that case, the function can be called as math['var'](...) instead of math.var(...).

Syntax #

math.var(a, b, c, ...)
math.var(A)
math.var(A, normalization)
math.var(A, dimension)
math.var(A, dimension, normalization)

Parameters #

Parameter Type Description
array Array | Matrix A single matrix or or multiple scalar values
normalization string Determines how to normalize the variance. Choose ‘unbiased’ (default), ‘uncorrected’, or ‘biased’. Default value: ‘unbiased’.

Returns #

Type Description
* The variance

Examples #

math.var(2, 4, 6)                     // returns 4
math.var([2, 4, 6, 8])                // returns 6.666666666666667
math.var([2, 4, 6, 8], 'uncorrected') // returns 5
math.var([2, 4, 6, 8], 'biased')      // returns 4

math.var([[1, 2, 3], [4, 5, 6]])      // returns 3.5
math.var([[1, 2, 3], [4, 6, 8]], 0)    // returns [4.5, 8, 12.5]
math.var([[1, 2, 3], [4, 6, 8]], 1)    // returns [1, 4]
math.var([[1, 2, 3], [4, 6, 8]], 1, 'biased') // returns [0.5, 2]

See also #

mean, median, max, min, prod, std, sum

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